Grinding machine



Filed March 24, 1924 jgl;

latented Dec. 9, 1930 FREDERIC E. GARDNER,

PATENT OFFICE F BELOIT, WISCONSIN GRINIDING MACHINE Appiieation inedMarch 24,

This invention relates to an improvement in work carriers for machinetools,l and has particular reference to an improved carrier for feedingthin work blanks between the opposed faces of a pair of operatingelements.

I have shown the invention applied to a grinding machine similar ingeneral arrangement and operation to the Vmacl ine disclosed in mycopending application Serial No. lli-7l, 585 filed June 3, 1921 (atentNo. 1,649,823, issued Nov. 22, 1927). In that machine, the work blanksare fed by a reciprocating carrier between the overlapping faces of twoopposed grinding wheels arranged in offset re lation. When grinding verythin work blanks,such as piston rings, thrust collars and the like,which are 1/8 to g of an inch in thickness, an extremely i thin carrieris re'- quired. Heretofore, carriers if made too thin have oener-all'been unsatisfactor i in that they were flexible and would bend whensubjected to an end push, thereby being forced into accidental contactwith the grinding wheels, and resulting in a consequent warping,distortion, and weakening of the metal.

rhe primary object of the presentinvention therefore is to provide awork carrier for very thin blanks which will not flex o-r bendmaterially in operation.

A more detailed object is to provide a thin flexible work carrier forfeeding blanks between the opposed faces of two or more operatingelements, said carrier being under constant tension in any direction ofmovement, thereby preventing flexure or undue bending of said carrieragainst said operating element.

Ancillary objects and advantages will become apparent as the descriptionproceeds.

ln the accompanying drawings, Figure 1 is a fragmentary and partiallydiagrammatic view of a machine embodying` the features of my invention,the view being' partially in end elevation and partially in sectionalong line i-i of Fig. a.

Fig. 2 is a fragmentary sectional view taken in the plane of line 2-2 ofFig. 1, and showing a plan view of the carrier proper.

Referring to the drawings, the grinding machine comprises generally amain base 10 1924., serialNo. 701,357.

on the opposite ends of which a pair of spindle carriages 11 are mountedin oll'set relation. Two parallel spindles 12 are journaled in thecarriages 11, and are driven by any suitable means (not shown). Heads 13are secured to the adjacent ends of the spindles 12, and support a pairof annular grinding disks or wheels 14 which overlap to the extent oftheir annular width. The central apertures of the grinding wheels areclosed by a pair of guards 15 which are adjustably supported by rods 16extending through the spindles 12.

lVork is periodically fed between the overlapping faces of the grindingwheels 111 by a carrier comprising a thin reciprocating strip 17 havingan aperture or pocket 18 for holding the work blank 19. The strip 17 issuitably supported and guided at its opposite ends b-y brackets 2Osecured' to the machine base 10.

Any suitable means may be provided for reciprocating the carrier` In thepresent instance, the driving end of the strip 17 is pivotally connectedby a horizontal link 21 to the upper end of a vertical lever 22. Thelever 22 is mounted at its lower end for oscillation upon a stationaryshaft 23 on the base 10, and is formed rigid with a short lever arm 24similarly mounted. At its upper end, the lever arm 24; is pivotallyconnected by a substantially horizontal link 25 to a power disk 26mounted on a shaft 27. The shaft 27 is journaled in the base 10, and isdriven by any suitable means (not shown). It will be seen that as thedisk 26 revolves, .the lever 22 will o be oscillated and the strip 17reciprocated, the rate of movement of each being the greatest while thework blank is passing between the wheels 14. rl`he work blanks areinserted into the aperture 18 when the strip 17 is in an extremeposition, and are ejected therefrom when the strip is in the otherextreme position.

Means is provided for tensioning the strip 17 to prevent accidentalcontact thereof with the faces of the guiding wheels 1/1. In the presentinstance, a flexible cable 28 is secured to the free end of the strip17, extends over a pulley 29 supported by an outwardly extending bracket30 on the base 10, and carries a Yce ythe carrier yfrom contacting withthe faces of the grinding wheels, and increasing its life. The carrieris simple in construction and efficient in operation.

While I have illustrated my invention with considerable particularity,it is to be understood that various modilications and alternativeconstructions may be made Withoutdepart-ing from the spirit and scope oithe invention as expressed in the appended claims.

I claim as my invention 1. A grinding machine comprising, incombination, a base, a pair ot annulargrinding disks disposed inparallel relation and positioned to overlap to the extent oi theirradial depth, a relatively thin wide flexible work carrier mountedforreciprocation between said disks with the width parallel to thegrinding faces of said disks, said worky carrier being provided with anaperture for supportlng a work blank, power means engaging one end ofsaid carrier for periodically drawing the carrier outwardly in one direction, and yielding means engaging theopposite end of said carrier tooppose the action of said first mentioned means.

Q. A grinding machine having, inY combination, a base, apair of annulargrinding disks disposed in parallel relation and positioned tooverlap tothe extent of their radial depth, a thin flat flexible strip betweensaid disks with the width of said strip parallel to the grinding faces,said strip'being constructed to support a work blank, means on said basefor guiding said stri p in its reciprocation between said grindingdisks, a weight secured to one end of said strip and tendingcontinuously to draw said strip in one direction, and a power meansengaging the other on d of said strip and adapted to periodically drawsaid strip in the other direction whereby said. strip is maintained tautto prevent lexure againsr the faces of said grinding disks. y I

3. A grinding machine having, in combination, a grinding element, aflexible 'fiat strip mounted for reciprocation across the face of saidelement with the width oit' said strip being disposed/toward said tace,said strip being constructed to suitably carry a work blank, meanscooperating with said strip to retain said work blank in position, meansengaging one end of saidstrip and tending to Vdraw the lattercontinuously in one direction, and power means engaging the other end ofsaid strip Yfor periodically moving said strip in the opposite directionwhereby the strip is held taut trol the position of said strip.

5. Ina machine of the class described, in

combination, a base, an operating element having a flat face mounted onsaid base, a thin iat flexible work carrier strip for carrying a workblank positioned for movement across said face, the width of said stripbeing prosented to said face, means on said base for guiding said stripin its movement, a weight secured'to one end of said strip and tendingcontinuously to draw said strip in one direction across said face, andpower means engaging the other endof said strip and adapted toperiodically, draw said strip in the otherjdirection.

6;.A machine of the character described having, in combination, a base,an operating element on said base, a thin fiat work carrier strippositioned for reciprocatory movement across said operating Yelement andhaving means for supporting the work, the dat ofthe strip beingpresented to said element, a pair of guide brackets'supportedon saidbase at opposite sides ot said operating element for guiding said stripin its reciprocation, power means engaging one end of said strip, andyielding means engaging the other end of said strip and tending to movesaid strip in one direction.

In testimony whereof, I have hereunto affixed my signature.

FREDERIC E. GARDNER.

element, a thin flat flex-y ICS

